Surf and turbulent water have always been a danger to mariners and beachgoers. This invention is directed to addressing this long standing problem by improving on prior art.
Shallow draft rowing surf rescue boats that operate in surf and turbulent waterways have a particular advantage in using an open tubular chassis and frame, a payload platform, radially adjustable tube struts, and independent adjustable starling control assemblies. In certain embodiments, the invention provides a modular apparatus and methods to substantially reduce a vessel's wetted surface areas and total weight; to increase the operator's active control of the location and amount of vessel buoyancy forces as well as their orientation to the vessel's center line and amidships thereby better controlling the movements of the vessel's center of buoyancy, center of gravity, metacenter and its resulting righting moment; and to enable operator modification to accommodate the invention to local surf, tide, current, and waterway conditions better than prior art.
In general marine usage, the ratio of the craft's length overall (LOA) to its beam on center (BOC) line (LOA/BOC) is used to estimate the stability of vessels. For purposes of this application, Overall Aspect Ratio (OAR) will be used interchangeably with LOA/BOC and variable aspect will indicate the invention's ability to change the OAR as defined herein. Length overall, often abbreviated as LOA, is the maximum length of a vessel's hull measured parallel to the waterline. The beam of a ship is its width at the widest point as measured at the ship's nominal waterline.
The present invention operates with either a high or low OAR as selected by the operator. The present invention has multiple hulls (or flotation starlings) which are attached by radially angled struts that may be extended or retracted to vary the craft length and beam in relation to the craft's center line. The present invention is unique and superior to prior art watercraft in that its operator can vary both its length overall and its beam on center resulting in an OAR of 0.73:1 to 11:1 which provides the operator superior control in responding to varying waterway conditions.
In certain embodiments, the invention provides a modular apparatus and methods to substantially reduce a vessel's wetted surface areas and total weight; to increase the operator's active control of the location and amount of vessel buoyancy forces as well as their vector orientation to the vessel's center line amidships thereby better controlling the movements of the vessel's center of buoyancy, center of gravity, metacenter and its resulting righting moment; and to enable operator modification to accommodate the invention to local surf, tide, current, and waterway conditions better than prior art.
Where prior art outrigger canoe, catamaran and trimaran watercraft connect their outrigger, pontoon, float, or multi-hull with lateral beams to form a fixed, rectilinear geometry, the invention's modular flotation starlings, adjustable tube struts, radially adjustable chassis and frame components allow the invention to vary its buoyancy and its geometry.
When prior art surf boats traverse a short period, steep wave, they pitch forward, sideways or slide backward as their center of gravity crosses the wave peak which creates rapid rotation, then acceleration as the craft moves down the other side of the wave. When the present invention traverses similar short period, steep waves, the invention's novel construction allows the lifting forces to pass through the vessel superstructure and avoid the rapid acceleration forces and rotation experienced by prior art vessels. The invention embodying the improvements described below maintains a stable profile which more safely navigates similar turbulence and cresting waves than prior art craft and offers the operator novel and improved methods of craft operation and navigation.